U.S. Pat. No. 3,709,552 issued Jan. 9, 1973 discloses a truck van having an open side which is closable by a slidable curtain suspended from the roof of the van body.
U.S. Pat. No. 4,545,611 issued Oct. 8, 1985 discloses a van body having pleated sides which afford side openings which are closable by slidable door structure consisting of two solid end doors interconnected and bridged by a foldable curtain.
U.S. Pat. No. 4,844,524 issued July 4, 1989 discloses a truck trailer closure assembly for tensioning a flexible curtain over an opening which includes a shaft with a vertical axis together with bearing members rotatably connecting the shaft to the truck trailer.